It is presented here that even though the use of the inflatable-deflatable compression arm-cuff working in conjunction with the rubber bulb, the air-valve regulator, and either the mercury or aneroid manometer has been widely accepted for several decades to achieve the non-invasive clinical measurements of human blood pressure, it has been found to have many disadvantages because of the following reasons:
(1) Longer time frame involved in the operation of the device causing pain, numbness and tingling sensations on the part of the subject experiencing the said sensations below the compression area of the pressurized limb such as the upper arm.
(2) Unnecessary prolonged periods of repeated extravascular compression causing blood flow impedance, not only to the venous blood return from below the compression area, but also to the general arterial and capillary circulatory vessels therearound the said compression points.
(3) The compression arm-cuff, having a constant width, is not always optimally applicable to a variety of arm diameters of various individuals thus causing erroneous results.
(4) If the arm-cuff has been placed too loosely around the limb, such as the upper arm, there results an erroneously high reading.
(5) If the arm-cuff is placed around the upper arm too tightly, there results a significant low reading of the blood pressure measurement.
(6) The arm-cuff is time-consuming and awkward to manipulate, especially for self application by the subject, or by application of others to the patient.
(7) The air-valve regulator sometimes gets stuck, thus there is danger of having a prolonged period of arm-cuff compression therearound the subject's limb until the stuck air-valve has been loosened.
(8) The arm-cuff and the associated rubber bulb and air-valve regulatory mechanism add more cost and greater bulk to the device, and the tubings coordinating them to the mercury or aneroid gauges sometimes get entangled during the operation of the device.
For these reasons, the instant invention has been invented to help solve the disadvantages of the blood pressure device utilizing the said compression arm-cuff and associated regulatory mechanisms, and to solve a tremendous demand by the public for a more portable, fast, and cuffless blood pressure system integrated with the most advanced electronic micro-circuitry with data-time-date memory entry and retrieval, so that a device such as this can bring forward right at the fingertips of the users around the world, an easily operable and informative device that is reliable and accurate for both self-application and applications to others in the hospitals, clinics, doctors offices, and most especially, for home use and during travel, because hypertension afflicts a large segment of the worldwide population, being the top ranking disabling and killer ailment of this century.
In the United States alone, according to the estimates of the National Heart, Lung, and Blood Institute, there are about 35 million Americans with definite hypertension and approximately 25 million Americans having borderline hypertension.
In accordance with the 1978 data from the National Center of Health statistics; National Heart, Lung, and Blood Institute; National Cancer Institute; American Cancer Society; Arthritis Foundation and the National Institute of Arthritis, Metabolism and Digestive Diseases, hypertension is the most prevalent of the chronic diseases (in millions of patients) as compared to other chronic diseases such as arthritis, heart disease, mental illness, visual impairment, spine impairment, chronic bronchitis, asthma, diabetes, stomach ulcer, and cancer.
According to the 12-year study by the Public Health Service in Framingham, Mass., wherein 5,209 men and women ranging from the ages of 35 to 74 were examined, and the health records of those with high blood pressure and those having normal blood pressure comparatively analyzed, 3 important findings resulted:
(1) Those with high blood pressure had more than 6 times as many heart failures.
(2) More than seven times as many strokes compared with those having normal blood pressure readings.
(3) 3 times as many heart attacks compared to the normal blood pressure group.
It is, therefore, very important that since hypertension causes many serious and frequently fatal complications, and that since it is usually a "silent" or asymptomatic disease developing for relatively longer periods, it is of utmost necessity that blood pressure measurements be frequently made in order to assure the population on their current blood pressure readings so as to give the necessary and proper treatment for preventing complications and to prevent the development of the disease by regulatory measures such as a change in lifestyle as well as change in diet.